One technique is to play the bottom note with your pick and the top with one of your free fingers. I've seen Eric Johnson and other do this. The helpful thing is that you can play these types of chords without having that *click* from muted strings in between or having to "hide" your pick for a second (I personally like to keep my pick kind of in my mouth while fingerpicking).
"You must stab him in the heart with the Bone Saber of Zumacalis... well, you could stab him in the head or the lungs, too... and the saber, it probably doesn't have to be bone, just anything sharp lying around the house... you could poke him with a pillow and kill him."
- Aqua Teen Hunger Force, The Universal Re-Monster